Swegon Air Academy seminar took the place on November 22 in Tallinn, Estonia. And it was all about renovation possibilities in multi-residential buildings. Åsa Wahlström shared her experiences with Swedish situation and what kind of measures can be applied in energy-efficient and cost-effective way in Swedish multi-residential buildings. And this topic was right on the time as this year Estonia is deep in renovation of buildings!
One of the Estonian participants was able to give a small insight in current situation in Estonia: “Estonia has sold almost 147 million worth of unused carbon credits to Japanese companies in several deals and according the CO2 quota buyers, the money has to be spent on energy efficiency improvements of public buildings, including schools, municipal and other governmental buildings. By November, more than 29 public buildings all over Estonia have been renovated and by the end of next year, additional 451 buildings have to be refurbished.”
Åsa started with discribing situation in Sweden where the total energy use in Sweden accounts for 410 TWh annually and the apartment buildings use up to 42 TWh, i.e. heating and production of hot water 28 TWh, and operation and domestic electricity equal to 14 TWh. In Sweden, all heating energy and domestic hot water (DHW) come from district heating, where 90% of heating in multi-residential buildings originates from district heating (based on waste burning, hydro and nuclear power), only 1% of buildings is heated by oil, and only little heating is provided from sources of electricity, biofuel and pellets. In Sweden, the multi-residential buildings are built mostly as concrete slab blocks and often the buildings are low-rise apartment buildings with 3-4 storeys and they are long in a row. There are also higher blocks of flats up to 8-12 storeys and also built as long row buildings with multiple entrances. Still the majority of buildings have only 4 floors as the building regulation for buildings with five storeys or more requires the building to have a lift which is expensive.
In period of 1965-1971, one million apartments were required by the government in Sweden. This was called Million Programme or Miljönprogram in Swedish. It was a political decision, but strategically positioned in time as the industry was already in place. Altogether there are total of 2.4 million apartments built in Sweden. In current situation, over 75% of all apartments will need renovation before year 2015 and most of them need renovation right now. It is estimated that every year over 50,000 apartments need to be renovated to cover the needs. And it is estimated that it will cost approximately 2-5 billion EUR to make the renovations.
The national target for the building sector is to reduce the energy by 20% until year 2020 as the common European Union goal. The additional goal is to lower the energy consumption by 50% by year 2050 as extra effort in Sweden. In Sweden, the actual energy use has been stable in period from 1996 to 2010, but with heating degree-day correction it can be seen that there is a slight decrease in energy consumption. Yet, it still amounts to approximately 160-180 kWh/(m2.a). So far there have been applied only easy measures in Swedish buildings, but most of the costly measures are yet to come. Due to the European Directive, there is a new regulation in Sweden applied from 2013 which will deal with renovation of buildings in high quality focusing on indoor climate and energy performance. Here is the quote from the building regulation on quality issues: “The basis for quality requirements that should be applied during major renovation is the same as the ones at new constructions.”
Photo by Petra Vladykova